ELECTRICITY

A wire of length /, made of material resistivity ρ is cut into two equal parts. The resistivity of the two parts are equal to-

• ρ

• ρ2

• 2 ρ

• 4 ρ

The temperature of a conductor is increased. The graph best showing the variation of its resistance is-

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A battery of 10 volt carries 20,000 C of charge through a resistance of 20 Ω. The work done in 10 seconds is-

• 2 × 10³ joule

• 2 × 10⁵joule

• 2 × 10⁴ joule

• 2 × 10² joule

A boy records that 4000 joule of work is required to transfer 10 coulomb of charge between two points of a resistor of 50 Ω. The current passing through it is-

• 2 A

• 4 A

• 8 A

• 16 A

What will be The resistance whose V-I graph is given above..

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To get 2 Ω resistance using only 6 Ω resistors, the number of them required is-

• 2

• 3

• 4

• 6

Two wires of same length and area made of two materials of resistivity ρ₁ and ρ₂ are connected in series to a source of potential V. The equivalent resistivity for the same area is-

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Two devices are connected between two points say A and B in parallel. The physical quantity that will remain the same between the two points is-

• current

• voltage

• resistance

• None of these

The least resistance obtained by using 2 Ω, 4 Ω, 1 Ω and 100 Ω is

• < 100 Ω

• < 4 Ω

• < 1 Ω

• > 2 Ω

Two wires of same length and area, made of two materials of resistivity ρ₁ and ρ₂ are connected in parallel V to a source of potential. The equivalent resistivity for the same length and area is-

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